Event construction with movable pitch

ABSTRACT

An event construction comprises a public area, such as a grandstand, and a pitch for performing activities, for example sporting activities like football or baseball. The pitch is accommodated on a floor which by sliding elements is set up in such a way that it can be moved in relation to the public area. The sliding elements comprise at least one elongated track which is set up underneath the floor and is connected to the base or to the floor, and also supporting elements which are connected to the floor and can be slid in relation to the track, or supporting elements connected to the base, over which supporting elements the elongated track can be slid. Each track consists of mortar material.

CROSS REFERENCE TO RELATED APPLICATION

This application is the 35 USC 371 national stage of InternationalApplication PCT/NL98/00511 filed on Sep. 5, 1998 which designated theUnited States of America.

FIELD OF THE INVENTION

The invention relates to an event construction, comprising a publicarea, such as a grandstand, and a pitch for performing activities, forexample sporting activities like football and baseball, which pitch isaccommodated on a floor which by means of sliding means is set up insuch a way that it can be moved in relation to the public area, whichsliding means comprise at least one elongated track which is set upunderneath the floor and is connected to the base or to the floor, andalso supporting means which are connected to the floor and can be slidin relation to the track, or supporting means connected to the base,over which supporting means the elongated track can be slid.

BACKGROUND OF THE INVENTION

Such a construction is known from NL-A-9300182. A number of steelelements are accommodated in the base, which elements serve as slidetracks. These elements support a number of feet of a casing containing agrass mat. Each foot has at its bottom end a PTFE-containing plasticsheet, which is slidable with low friction over the steel element.

On the one hand, the steel elements must be sturdily supported in thebase, which can consist of, for example, a concrete foundation slab. Onthe other hand, small relative movements must be possible, in view ofpossible settlement and differences in expansion. The costs of such aconstruction are consequently relatively high.

SUMMARY OF THE INVENTION

The object of the invention is to provide a construction of theabovementioned type which does not have these disadvantages. That objectis achieved by the fact that each track consists of mortar material.

The tracks made of mortar material can be manufactured in a simplemanner with great accuracy as regards the levelness of the slidingsurface, and consequently provide an even support for the floor situatedabove, in which a pitch is accommodated. It is possible to treat thesurface area of the sliding surface after the mortar material has set,in such a way that the coefficient of friction is as low as possible.Such a treatment can be, for example, a polishing treatment.

An example which can be mentioned is a cast mortar based on plastic,such as an epoxy resin, which is preferably a two-component epoxy resin.

The mortar can also contain stony granules, such as sand or fine gravel,with a granule size between 0.25 and 4 mm. After the mortar material hasset, it must have the maximum compression strength, which lies between30 and 150 N/mm².

A reinforcement is preferably incorporated in the mortar material, inorder to increase the maximum permissible tensile load of the mortarmaterial. This gives the tracks good ability to withstand the tensileforces created in the tracks during shifting of the pitch

The tracks of mortar material can be sunk in the base, such as aconcrete slab. For that purpose, such a slab has a trench made in it,after which the reinforcement is placed in said trench and the mortarmaterial applied.

Furthermore, each track of mortar material can be covered with afriction-reducing paint layer.

In order to rule out the possibility of such a paint layer peeling offas a result of rising damp, the mortar when it has set must beimpermeable to vapour.

The paint layer can comprise a first coat and at least one top coat.This first coat and top coat can each consist of a two-component epoxyresin; the top coat can also contain wear-resistant pigments. After ithas dried, the paint layer must preferably be able to withstand amaximum surface pressure which lies between 5 and 80 N/mm². In addition,in the pull-off test the value obtained for this layer must preferablylie between 0.5 and 20 N/mm².

The thickness of the first coat preferably lies between 30 and 50 μm;that of a top coat between 120 and 350 μm.

Two or more top coats can also be provided, the total thickness of thepaint layers lying between 150 and 7000 μm. It is also possible toreverse the elongated track and the supporting means; the supportingmeans can be placed in or on the foundation slab, and the elongatedtrack can be fixed to and/or manufactured on the underside of themovable floor.

Another variant can consist of the supporting means comprising elongatedtracks, the sliding surface part of which is also made of mortarmaterial, which can further be provided with a friction-reducing paintlayer. In this variant both sliding surfaces can be made of mortarmaterial.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in greater detail with reference toan exemplary embodiment shown in the figures.

FIG. 1 shows a diagrammatic view of the construction according to theinvention, in perspective and partially in section.

FIG. 2 shows a detail according to II—II of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The event construction according to the invention shown in FIG. 1 is inthe form of a football pitch or hockey pitch. The construction comprisesa casing 1, in which a pitch 2 is accommodated. Said pitch 2 in theusual manner consists of sand and earth and a water drainage system, onwhich a grass mat is placed. The pitch 2 rests on the movable floor 3,which forms part of the casing 1.

By means of a number of feet 4, fixed to the floor 3, the casing 1 issupported on a number of elongated tracks 5.

In the playing position of the movable pitch 2, a grandstand 15 forspectators can be fitted in the vicinity of the pitch 2.

As shown in FIG. 2, the underside of each foot 4 is provided with alayer of teflon 6. The tracks 5 are provided on their top surface with apaint layer 7. The teflon sheets 6 and the paint layer 7 have a lowcoefficient of friction relative to each other. Said low coefficient offriction can be reduced even further by applying grease and/or oilbetween the contact faces of teflon sheets 6 and paint layer 7. As aresult of this, the pitch 2 can be slid in the casing 1 in the directionof the arrow in FIG. 1 by means of piston/cylinder devices (not shown).

The tracks 5 according to the invention each consist of a mortar, forexample a cast mortar 8 based on an epoxy resin, in which areinforcement 9 is incorporated.

The tracks 5 are accommodated in trenches 10 of the base 11. The base 11can be made of concrete in which a reinforcement 12 can be incorporated.

What is claimed is:
 1. An event construction, comprising: a public areafor viewing activities; a pitch for performing said activities; saidpitch being accommodated on a movable floor over a base; sliding meansstructured and arranged to move the pitch in relation to the publicarea; said sliding means comprising at least one elongated track locatedunderneath the movable floor and connected to at least one of the baseand the movable floor; each elongated track comprising mortar materialwhich is covered with a friction-reducing paint layer; and supportingmeans connected to at least one of the movable floor and the base, andstructured and arranged to slide in relation to the track.
 2. Theconstruction according to claim 1, wherein the mortar is a cast mortarbased on at least one of plastic and cement.
 3. The constructionaccording to claim 2, wherein the cast mortar is based on epoxy resin.4. The construction according to claim 3, wherein the epoxy resin is atwo-component resin.
 5. The construction according to claim 1, whereinthe mortar contains stony granules having a granule size between 0.25and 4 mm.
 6. The construction according to claim 1, wherein the mortaris impermeable to vapor after setting.
 7. The construction according toclaim 1, wherein after setting, the mortar has a maximum compressionstrength ranging between 30 and 150 N/mm².
 8. The construction accordingto claim 1, further comprising a reinforcement incorporated in themortar material, in order to increase the maximum permissible tensileload of the mortar material.
 9. The construction according to claim 8,wherein the reinforcement comprises bars extending in the lengthwisedirection of the track.
 10. The construction according to claim 1,wherein each track made of mortar material is recessed in the base orthe bottom of the floor.
 11. The construction according to claim 1,wherein after drying, the paint layer can withstand a surface pressureranging between 5 and 80 N/mm².
 12. The construction according to claim1, wherein after drying, the paint layer can withstand a pull-offstrength ranging between 0.5 and 20 N/mm².
 13. The constructionaccording to claim 1, wherein the paint layer comprises a first coat andat least one top coat.
 14. The construction according to claim 13,wherein the first coat and each top coat comprises a two-component epoxyresin.
 15. The construction according to claim 14, wherein said at leastone top coat contains wear-resistant pigments.
 16. The constructionaccording to claim 13, wherein the first coat has a thickness rangingbetween 30 and 50 μm.
 17. The construction according to claim 13,wherein said at least one top coat has a thickness ranging between 120and 350 μm.
 18. The construction according to claim 13, wherein two topcoats are provided, and the total thickness of the paint ranges between150 and 7000 μm.
 19. The construction according to claim 13, wherein twotop coats are provided, and the total thickness of the paint layersranges between 150 and 500 μm.
 20. The construction according to claim1, wherein the supporting means comprise a foot having an underside anda top side; said foot being covered at least on the underside or on thetop side with a PTFE-containing plastic.
 21. The construction accordingto claim 1, wherein each track consists exclusively of mortar materialand a paint layer.